Final answer:
Bryophytes reproduce with specialized organs; antheridia for sperm and archegonia for eggs. Fertilization requires water for sperm to swim to the egg. The resulting sporophyte produces haploid spores for the next generation of gametophytes.
Step-by-step explanation:
In bryophytes, the male and female reproductive organs are known as antheridia and archegonia, respectively. Sperm are produced in the antheridia, whereas eggs are produced in the archegonia. To facilitate fertilization, sperm need a moist environment such as standing water to swim to the egg cells. Fertilization occurs when sperm swim through water to reach and enter an archegonium, where they fertilize the egg. The result is a zygote that grows into a sporophyte, which is nutritionally dependent on the gametophyte, the larger, haploid phase of the bryophyte life cycle.
The archegonia are flask-shaped structures with a base where a single egg resides. Attractant chemicals guide the sperm down the neck of the archegonium to reach the egg for the process of fertilization. Post-fertilization, the protected zygote divides and grows into a sporophyte that remains physically connected to the gametophyte. The sporophyte eventually produces haploid spores through meiosis, which disperse to give rise to a new generation of gametophytes.
The rhizoids of bryophytes help anchor the plant and are sometimes only one cell thick. Bryophyte life cycles are heavily dependent on water not just for the mobility of the sperm, but also for the dispersion of spores. This reliance on a moist environment is a significant aspect of their ecology and reproductive strategy.